#!/usr/bin/env python
from smbus2 import SMBus
from collections import namedtuple

# https://datasheets.maximintegrated.com/en/ds/MAX98089.pdf

AmpConfig = namedtuple('AmpConfig', ['name', 'value', 'register', 'offset', 'mask'])
EQParams = namedtuple('EQParams', ['K', 'k1', 'k2', 'c1', 'c2'])

def configs_from_eq_params(base, eq_params):
  return [
    AmpConfig("K (high)", (eq_params.K >> 8), base, 0, 0xFF),
    AmpConfig("K (low)", (eq_params.K & 0xFF), base + 1, 0, 0xFF),
    AmpConfig("k1 (high)", (eq_params.k1 >> 8), base + 2, 0, 0xFF),
    AmpConfig("k1 (low)", (eq_params.k1 & 0xFF), base + 3, 0, 0xFF),
    AmpConfig("k2 (high)", (eq_params.k2 >> 8), base + 4, 0, 0xFF),
    AmpConfig("k2 (low)", (eq_params.k2 & 0xFF), base + 5, 0, 0xFF),
    AmpConfig("c1 (high)", (eq_params.c1 >> 8), base + 6, 0, 0xFF),
    AmpConfig("c1 (low)", (eq_params.c1 & 0xFF), base + 7, 0, 0xFF),
    AmpConfig("c2 (high)", (eq_params.c2 >> 8), base + 8, 0, 0xFF),
    AmpConfig("c2 (low)", (eq_params.c2 & 0xFF), base + 9, 0, 0xFF),
  ]

BASE_CONFIG = [
  AmpConfig("MCLK prescaler", 0b01, 0x10, 4, 0b00110000),
  AmpConfig("PM: enable speakers", 0b11, 0x4D, 4, 0b00110000),
  AmpConfig("PM: enable DACs", 0b11, 0x4D, 0, 0b00000011),
  AmpConfig("Right speaker output from right DAC", 0b1, 0x2C, 0, 0b11111111),
  AmpConfig("Right Speaker Mixer Gain", 0b00, 0x2D, 2, 0b00001100),
  AmpConfig("Enable PLL1", 0b1, 0x12, 7, 0b10000000),
  AmpConfig("Enable PLL2", 0b1, 0x1A, 7, 0b10000000),
  AmpConfig("DAI1: I2S mode", 0b00100, 0x14, 2, 0b01111100),
  AmpConfig("DAI2: I2S mode", 0b00100, 0x1C, 2, 0b01111100),
  AmpConfig("Right speaker output volume", 0x1c, 0x3E, 0, 0b00011111),
  AmpConfig("DAI1 Passband filtering: music mode", 0b1, 0x18, 7, 0b10000000),
  AmpConfig("DAI1 voice mode gain (DV1G)", 0b00, 0x2F, 4, 0b00110000),
  AmpConfig("DAI1 attenuation (DV1)", 0x0, 0x2F, 0, 0b00001111),
  AmpConfig("DAI2 attenuation (DV2)", 0x0, 0x31, 0, 0b00001111),
  AmpConfig("DAI2: DC blocking", 0b1, 0x20, 0, 0b00000001),
  AmpConfig("DAI2: High sample rate", 0b0, 0x20, 3, 0b00001000),
  AmpConfig("ALC enable", 0b1, 0x43, 7, 0b10000000),
  AmpConfig("ALC/excursion limiter release time", 0b101, 0x43, 4, 0b01110000),
  AmpConfig("ALC multiband enable", 0b1, 0x43, 3, 0b00001000),
  AmpConfig("DAI1 EQ enable", 0b0, 0x49, 0, 0b00000001),
  AmpConfig("DAI2 EQ enable", 0b1, 0x49, 1, 0b00000010),
  AmpConfig("DAI2 EQ clip detection disabled", 0b1, 0x32, 4, 0b00010000),
  AmpConfig("DAI2 EQ attenuation", 0x5, 0x32, 0, 0b00001111),
  AmpConfig("Excursion limiter upper corner freq", 0b100, 0x41, 4, 0b01110000),
  AmpConfig("Excursion limiter lower corner freq", 0b00, 0x41, 0, 0b00000011),
  AmpConfig("Excursion limiter threshold", 0b000, 0x42, 0, 0b00001111),
  AmpConfig("Distortion limit (THDCLP)", 0x6, 0x46, 4, 0b11110000),
  AmpConfig("Distortion limiter release time constant", 0b0, 0x46, 0, 0b00000001),
  AmpConfig("Right DAC input mixer: DAI1 left", 0b0, 0x22, 3, 0b00001000),
  AmpConfig("Right DAC input mixer: DAI1 right", 0b0, 0x22, 2, 0b00000100),
  AmpConfig("Right DAC input mixer: DAI2 left", 0b1, 0x22, 1, 0b00000010),
  AmpConfig("Right DAC input mixer: DAI2 right", 0b0, 0x22, 0, 0b00000001),
  AmpConfig("DAI1 audio port selector", 0b10, 0x16, 6, 0b11000000),
  AmpConfig("DAI2 audio port selector", 0b01, 0x1E, 6, 0b11000000),
  AmpConfig("Enable left digital microphone", 0b1, 0x48, 5, 0b00100000),
  AmpConfig("Enable right digital microphone", 0b1, 0x48, 4, 0b00010000),
  AmpConfig("Enhanced volume smoothing disabled", 0b0, 0x49, 7, 0b10000000),
  AmpConfig("Volume adjustment smoothing disabled", 0b0, 0x49, 6, 0b01000000),
  AmpConfig("Zero-crossing detection disabled", 0b0, 0x49, 5, 0b00100000),
]

BASE_CONFIG += configs_from_eq_params(0x84, EQParams(0x274F, 0xC0FF, 0x3BF9, 0x0B3C, 0x1656))
BASE_CONFIG += configs_from_eq_params(0x8E, EQParams(0x1009, 0xC6BF, 0x2952, 0x1C97, 0x30DF))
BASE_CONFIG += configs_from_eq_params(0x98, EQParams(0x0F75, 0xCBE5, 0x0ED2, 0x2528, 0x3E42))
BASE_CONFIG += configs_from_eq_params(0xA2, EQParams(0x091F, 0x3D4C, 0xCE11, 0x1266, 0x2807))
BASE_CONFIG += configs_from_eq_params(0xAC, EQParams(0x0A9E, 0x3F20, 0xE573, 0x0A8B, 0x3A3B))

class Amplifier:
  AMP_I2C_BUS = 0
  AMP_ADDRESS = 0x10

  def __init__(self, debug=False):
    self.debug = debug

  def set_config(self, config):
    with SMBus(self.AMP_I2C_BUS) as bus:
      if self.debug:
        print(f"Setting \"{config.name}\" to {config.value}:")

      old_value = bus.read_byte_data(self.AMP_ADDRESS, config.register, force=True)
      new_value = (old_value & (~config.mask)) | ((config.value << config.offset) & config.mask)
      bus.write_byte_data(self.AMP_ADDRESS, config.register, new_value, force=True)

      if self.debug:
        print(f"  Changed {hex(config.register)}: {hex(old_value)} -> {hex(new_value)}")

  def set_global_shutdown(self, amp_disabled):
    self.set_config(AmpConfig("Global shutdown", 0b0 if amp_disabled else 0b1, 0x51, 7, 0b10000000))

  def initialize_configuration(self):
    self.set_global_shutdown(amp_disabled=True)

    for config in BASE_CONFIG:
      self.set_config(config)

    self.set_global_shutdown(amp_disabled=False)


if __name__ == "__main__":
  Amplifier(debug=True).initialize_configuration()
